Physics Revision Flashcards
What is a thermistor?
A thermistor is a resistor that is dependent on the temperature. E.g. in hot conditions, the resistance falls and vice versa.
What is an LDR
An LDR (light dependent resistor) is a resistor that is dependent on the intensity of the light. E.g. in bright light, the resistance falls and vice versa.
What’s the formula for energy?
Energy = Power x Time
Or
E(Joules) = p(Watts)t(seconds)
What’s formula for work done?
Work done = Force x Distance
Or
W(Joules) = f(neutons)s(metres)
What’s the formula for GPE?
Gravitational potential energy
= Mass x Gravitational x height
field strength
Or
U(Joules) = m(Kg)g(N/kg)h(metres)
Give every type of electromagnetic radiation from the electromagnetic spectrum in order.
Radio waves Microwaves Infrared Visible light UV rays X-rays Gamma rays
Equation for charge.
Charge = current x time
Q = IT
Coulomb’s (C) = Amps (A) x Seconds (s)
Equation for potential difference (p.d.).
P.d. = Current x Resistance
V = IR
Volts (V) = Amps (A) x Ohms
What’s the difference between a step up and step down transformer?
Step up transformers are used to step up the size of the alternating potential difference. Whereas step down transformers do the opposite.
What’s the difference between alternating current and direct current?
AC is when electric current in a circuit repeatedly reverses its direction, whereas DC is when electric current in a circuit flows in one direction only.
What is the voltage of the mains electricity in the UK?
230V
Why is alpha radiation dangerous inside the human body?
Alpha radiation is highly ionising.
Alpha particles and gold nuclei are both positively charged. The gold nucleus _______ the alpha particles.
Repels
What does reproducible mean?
Another scientist repeats the same experiment and gets the same results.
Give 5 examples of renewable energy.
Solar energy Wind energy Hydroelectric energy Geothermal energy Tidal energy
